Optical exposure method, device manufacturing method and lithographic projection apparatus

Abstract

An optical exposure method carried out on a substrate that is at least partially covered by a layer of radiation-sensitive material, the method comprising: providing a plurality of projection beams of radiation; a first irradiating step of irradiating a peripheral annulus of the layer of radiation-sensitive material with a first one of said projection beams; and a second irradiating step of irradiating at least one inner portion of the radiation-sensitive material situated nearer the center of the substrate than the inner periphery of the outer region with a second one of said projection beams; wherein said first and second irradiating steps are carried out with the substrate positioned at the same location. The method can be used for edge bead removal (both coarse and fine detail) and marker clearout at a single station. Stencils can be used to modify the shape and size of the irradiating steps. Such a method can be incorporated as a part of a device manufacturing method but can be used as an single method. A lithographic projection apparatus can be adapted to apply this method, and the main projection apparatus beneficially shares metrology data with the optical exposure apparatus.

What is claimed is:  
     
       1. An optical exposure method carried out on a substrate that is at least partially covered by a layer of radiation-sensitive material, the method comprising: 
       providing a plurality of projection beams of radiation;  
       irradiating a peripheral annulus of the layer of radiation-sensitive material with a first one of said projection beams; and  
       irradiating at least one inner portion of the radiation-sensitive material situated nearer the center of the substrate than the inner periphery of the peripheral annulus with a second one of said projection beams;  
       wherein said irradiating a peripheral annulus and said irradiating at least one inner portion are carried out with the substrate positioned at the same location.  
     
     
       2. An optical exposure method according to  claim 1 , wherein at least one of the at least one irradiated inner portion of the layer of radiation-sensitive material is adjacent to the irradiated peripheral annulus of the layer of radiation-sensitive material. 
     
     
       3. An optical exposure method according to  claim 1 , wherein at least one irradiated inner portion of the layer of radiation-sensitive material is a rectangular shape. 
     
     
       4. An optical exposure method according to  claim 1 , wherein at least one of the at least one irradiated inner portion of the layer of radiation-sensitive material contains an alignment mark on the substrate. 
     
     
       5. An optical exposure method according to  claim 1 , wherein at least one of the at least one irradiated inner portion of the layer of radiation-sensitive material contains a wafer identification mark. 
     
     
       6. A device manufacturing method comprising: 
       providing a substrate that is at least partially covered by a layer of radiation-sensitive material;  
       providing a plurality of projection beams of radiation;  
       using patterning structure to endow at least one of the projection beams with a pattern in its cross-section;  
       projecting the at least one patterned beam of radiation onto a target portion of the layer of radiation-sensitive material; and  
       performing clearout of a portion of the layer of radiation-sensitive material not exposed in projecting the at least one patterned beam of radiation onto a target portion of the layer of radiation-sensitive material, said performing clearout including:  
       irradiating a peripheral annulus of the layer of radiation-sensitive material with a first one of said projection beams; and  
       irradiating at least one inner portion of the radiation-sensitive material situated nearer the center of the substrate than the inner periphery of the peripheral annulus with a second one of said projection beams;  
       wherein said irradiating a peripheral annulus and said irradiating at least one inner portion are carried out with the substrate positioned at the same location.  
     
     
       7. A lithographic projection apparatus comprising: 
       a main projection apparatus including,  
       a first radiation system to provide a first projection beam of radiation,  
       a support structure to support patterning structure, the patterning structure serves to pattern the first projection beam according to a desired pattern,  
       a first substrate table to hold a substrate, and  
       a first projection system to project the patterned first projection beam onto at least a target portion of the substrate; and  
       an optical exposure apparatus including,  
       a second radiation system to provide a second beam of radiation, the second radiation system embodied to provide a plurality of secondary component beams of radiation,  
       a second substrate table to hold a substrate, the second substrate table can be rotated parallel to a plane of the substrate,  
       a second projection system to project said second beam onto a portion of said substrate, the second projection system correspondingly comprises a plurality of secondary component projection systems, each of which serves to project one of said secondary component beams onto the substrate, and  
       at least one of said secondary component projection systems is flexible in such a manner that an extremity thereof proximal the substrate can be displaced in a direction parallel to the plane of the substrate, while an extremity thereof distal the substrate remains fixed relative to said plane; and  
       wherein the optical exposure apparatus and the main projection apparatus share metrology data.  
     
     
       8. A lithographic projection apparatus according to  claim 7 , wherein the said proximal extremity of said secondary component projection system is displaceable radially with respect to the plane of the substrate. 
     
     
       9. A lithographic projection apparatus according to  claim 7 , wherein each of the said secondary component projection systems is flexible in the said manner. 
     
     
       10. A lithographic projection apparatus according to  claim 7 , wherein at least one of the secondary component projection systems comprises a flexible light guide. 
     
     
       11. A lithographic projection apparatus according to  claim 10 , wherein the flexible light guide comprises a liquid-filled light guide. 
     
     
       12. A lithographic projection apparatus according to  claim 7 , wherein stencil holders are located between said second radiation system and said second substrate table, such that the radiation traversing each secondary component projection system can be provided with a stencil pattern. 
     
     
       13. A lithographic projection apparatus according to  claim 12 , wherein: 
       said plurality of secondary component projection systems is two secondary component projection systems;  
       each stencil pattern comprises an aperture in an opaque field;  
       the aperture for one of the secondary component projection systems is larger than for the other secondary component projection system.  
     
     
       14. A lithographic projection apparatus according to  claim 8 , wherein said second radiation system comprises a cloverleaf lens. 
     
     
       15. A lithographic projection apparatus according to  claim 8 , wherein the optical exposure apparatus is provided with an alignment sensor to measure the position and orientation of the substrate with respect to the rotational axis of the second substrate table. 
     
     
       16. A lithographic projection apparatus according to  claim 15 , wherein the optical exposure apparatus further comprises a substrate moving device to adjust said position and/or orientation of the substrate on the second substrate table. 
     
     
       17. A lithographic projection apparatus according to  claim 7 , further comprising a substrate handling station wherein said optical exposure apparatus is adjacent to said substrate handling station. 
     
     
       18. A lithographic projection apparatus according to  claim 7 , further comprising a substrate handling station wherein said optical exposure apparatus is within said substrate handling station. 
     
     
       19. A lithographic projection apparatus comprising: 
       a main projection apparatus, said main projection apparatus including  
       a first radiation system to provide a first projection beam of radiation,  
       a support structure to support patterning structure, the patterning structure serves to pattern the first projection beam according to a desired pattern,  
       a first substrate table to hold a substrate, and  
       a first projection system to project the patterned first projection beam onto at least a target portion of the substrate;  
       an optical exposure apparatus, said optical exposure apparatus including  
       a second radiation system to provide a second beam of radiation, the second radiation system embodied to provide a plurality of secondary component beams of radiation,  
       a second substrate table to hold a substrate, the second substrate table can be rotated parallel to a plane of the substrate,  
       a second projection system to project said second beam onto a portion of said substrate, the second projection system correspondingly comprises a plurality of secondary component projection systems, each of which serves to project one of said secondary component beams onto the substrate, and  
       at least one of said secondary component projection systems is flexible in such a manner that an extremity thereof proximal the substrate can be displaced in a direction parallel to the plane of the substrate, while an extremity thereof distal the substrate remains fixed relative to said plane; and  
       a beam splitting device configured to divert a portion of the first projection beam into the second radiation system of the optical exposure apparatus to create said second radiation beam.  
     
     
       20. A lithographic projection apparatus according to  claim 7 , further comprising a focusing system, the focusing system comprising; 
       at least one lens; and  
       at least one spacer; and  
       wherein the focusing system is self-aligning. 
     
     
       21. The optical exposure method according to  claim 1 , further comprising developing the irradiated at least one inner portion of the radiation-sensitive material. 
     
     
       22. The optical exposure method according to  claim 1 , wherein said irradiating at least one inner portion of the radiation-sensitive material terminates without removal of the irradiated at least one inner portion of the radiation-sensitive material from the substrate.